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OK, I'll note the following:

1. Avoid Dell computers like the plague. While XP should not lock up or BSoD I have seen these relatively regularly on Dell computers at work and therefore I don't think very highly of them. I'm sure that XP computers from other manufacturers have to be more reliable than these cheap 'n' cheerful boxes and laptops.

2. OS X is just as capable of screwing up if bad drivers are loaded. I installed Logitech's mouse drivers recently that caused kernel panics and so they were uninstalled. Apple tends to provide reliable drivers that won't cause these sorts of issues but even they aren't immune to this as a recent issue with new MacBook Pros and Airport networks illustrated.

However, I will say that after having switched about 4-years ago there's no way that I'd go back to Windows at the moment and that a major reason for this is that there's simply less hassle and frustration.
 
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